


Reunion of Brothers

by shiverfawkes



Series: Cumberbatch Crossover [1]
Category: Marvel Cinematic Universe, Sherlock (TV)
Genre: All of the spoilers, Alternate Universe - Twins, Crossover, Emotional Hurt/Comfort, First Meetings, Irondad, M/M, Parentlock, Post-Avengers: Infinity War Part 1 (Movie), Post-Episode: s04e03 The Final Problem, Spoilers
Language: English
Status: Completed
Published: 2018-11-15
Updated: 2018-11-15
Packaged: 2019-08-23 21:39:16
Rating: Not Rated
Warnings: Creator Chose Not To Use Archive Warnings, No Archive Warnings Apply
Chapters: 1
Words: 4,633
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/16626899
Author URL: https://archiveofourown.org/users/shiverfawkes/pseuds/shiverfawkes
Summary: "Its been seventeen years, surely you can't still be mad at me.""Surely I can. You left me Stephen."In which Sherlock Holmes and Stephen Strange are twins.





	Reunion of Brothers

**Author's Note:**

> This is absolute garbage, I started writing it, filled with adrenaline and then I realised how dumb the idea was and cringed at myself. 
> 
> if you enjoy it, thank you
> 
> if you don't, I honestly don't blame you
> 
> last spoiler warning, for both infinity war and sherlock.

John huffed out a sigh as he walked down the busy streets on the outskirts of New York City. He was surprised that he still hadn’t decided to yell at Sherlock for his constant effort to disappear for hours on end when they were on a case. He was following an address that Sherlock had texted him, presumably to discuss evidence or lack thereof.

The case had Sherlock spinning like a top, and now he was so close to solving it, he wasn’t taking answers nor orders from anybody. John was surprised he was even taking the time to talk to him now he was so riled up.

It turns out however, that New York was a lot bigger and more complicated than London, and he had no idea where he was going. He asked directions a few times but received conflicting answers, and gave up, not wanting to seem like an idiot English tourist. Though, that’s essentially what he was, had he not been there on business.

Eventually he found his way to Bleecker Street, which, if the map he had on his phone was any indication, was somewhere near to where he needed to be. At least he wasn’t entirely lost.

That problem solved itself when he caught sight of incredibly sharp cheek bones and nebula green eyes.

He breathed out a sigh of relief before furrowing his brow. “Christ what is he wearing- Sherlock!” John yelled across the street, but the taller man made no effort to respond, though ignoring John wasn’t anything knew that he’d done.

“Sherlock!” John called again, catching up as he ran toward him, he grabbed Sherlock’s arm to turn him round. “Sherlock you can’t just run away from me when we’re on a-“ This man was not Sherlock.

He had a goatee and swept back hair with a stripe of silvery grey woven into the sides. But his _face_ was most certainly Sherlock’s. Despite that, he refused to believe that Sherlock had grown facial hair in the span of five hours, and decided he’d made a mistake.

“Oh my god, I am so sorry-“ John was quick to apologise, removing his hand from Not-Sherlock’s arm. “I was just looking for my friend- you look like him- I’m sorry.”

“It’s alright.” Not-Sherlock was American, and he raised his hands in a peaceful manner, revealing an odd two finger ring and a plethora of scars, but John didn’t stare, instead choosing to focus on Not-Sherlock’s face. How could somebody look so similar to him? John had spent hours studying those cheekbones, eternities gazing into those eyes, he knew them. “Who were you looking for?”

“Oh- Uhm. His name’s Sherlock, Sherlock Holmes. I doubt you’ve heard of him, but he’s pretty big over in the UK.”

“I know him, quite well actually.”

John laughed, shaking his head. “That’s convenient considering you’re the closest lookalike I’ve ever seen.”

“Wrong, he’s a look alike of me, I was born first, alpha twin.” The man replied, checking a broken watch on his wrist and frowning.

John squeezed his eyes shut, pinching the bridge of his nose with an exasperated sigh, as the pieces clicked together in his head, no matter how improbable. “How many secret siblings can one man have? First _Eurus_ and now a twin?” His tone was annoyed, but he managed to keep the destructive rage internalised. Sherlock could guess him at any point in time, telling him every time he’d done in a day just by a scuff mark on his shoe. Yet he’d been dating the man for nearly two years, known him for a lot longer than that, and yet still had no idea that he had a bloody twin brother.  

“Believe me, I was a voluntary secret.”

“You two had a row then.” John replied, watching the taller man’s face carefully, he had a lot more clear tells than Sherlock, despite having the same face. John was right, he supposed noticing the flash of hurt in the taller man’s eyes. “I’d say fifteen years ago, maybe more. You miss him.”

Not-Sherlock laughed “Taught you well then.”

“I observed and learned.”

“Stephen, Dr Stephen Stark.” He held out a trembling hand for John to shake.   

“John, Dr John Watson.” The shorter man replied, taking his hand with his non-tremored one.  

“I know, we read your blog.”

“We?”

“My son and I, it’s a good way to keep up with how my brother’s doing, seeing as he cut off all contact with me.”

“Here.” John handed him his phone, the address pulled up on the screen, this time with the hand that shook, it was trembling for no good reason, but to some sort of twisted comfort, the other doctor took it with equally shaky fingers. “He wants me to meet him there, but I dunno how to get there. Take me and you can see him again. I know you want to.”

Not-Sherlock, now known as Stephen smiled, it seemed so strange to watch that expression come so clearly onto the face he’d trained himself to know as Sherlock’s, a smile that he rarely had the pleasure of seeing. “Sadly, you’re right, come on, it’s not too far from here.” He replied after reading the address, handing John his phone back.

He followed Not-Sherlock, now known as Stephen. He couldn’t help but shake his head at the clothes the taller man was wearing, they looked like a dungeons and dragons costume, with flowing robes and a bright red cloak, than John could’ve sworn had moved at its own will a couple times when he wasn’t looking.

He led John to a small café, Sherlock was sat on his phone, with two coffees in front of him, one his and the other presumably for John, and the doctor smiled as he sat down in front of the detective. Happy to see his sherlock, dressed in his deep purple dress shirt and two-piece suit.

“Took you long enough.” Sherlock muttered. “Yes, the coffees yours, no sugar.”

“Forgive me your highness, but I brought somebody you’d like to meet.” John replied taking a sip of his drink, and watching Sherlock across the table, not even glancing up to see.

“Dull, I doubt it, you can leave.” He waved his hand in Stephen’s general direction, still texting, still not looking.

John went to speak, but Stephen raised his hand to silence him. “That’s no way to greet your brother Lockie.”

The American accent caught him off guard, but he knew that voice anywhere, considering it was his own. It didn’t help that there was only one person in the world to ever call him Lockie.

Sherlocks expression wavered into shock and then fell into a scowl, which he directed at John - as if it was his fault - who rolled his eyes. Before speaking in the same disgusted tone he used when talking about predictability in movies and Anderson’s stupidity. “Oh, hello Stephenander. I suppose prearranged to his track record it would happen that John would find you, given the one in eight million chance.”

“Don’t play the full-name-game with me, William. It’s been seventeen years, surely you can’t _still_ be mad at me.”

“Surely I can. You left me Stephen, when I had nobody else. My own twin brother and you fucking abandoned me like I was worthless.” Sherlock slammed his fist on the table as his temper got the better of him and John swallowed, fearing for a moment that he’d made a grave mistake in trying to reunite the two.

“Oh you know that isn’t true.” Stephen replied, lacing his tone with poison just as easily as the detective had.

“Then what is the truth!? You ditched me, you ditched Mycroft, I was found on a drug overdose in a ditch after you left and you never even called!” Sherlock replied, his fists clenched, people were staring, people were listening but neither of them cared, because this fight had been a long time coming, avoided by blocked numbers and deleted emails and years of hiding from one another.

Stephen slammed his hand down on the table, John watched Sherlock’s gaze falter as his eyes traced over the scars on his fingers. “What do you want me to say Sherlock? Y’know what? I’m _so_ sorry that I hurt you, I’m sorry that I couldn’t get a job in London, and I'm sorry that I took the job here. But I don’t think you understand how much it hurts to be shut out for nearly two decades, and not even looked at when you make the effort to force yourself back in!” He yelled, caring the stares he attracted, and Sherlock was left unmoving, staring at his phone, though he wasn’t reading anything, he was just staring.

“Sherlock, look at me.” John spoke, his voice was soft, cutting through the venom with ease, and Sherlock’s scowl withered away as he took his hand. “Your brother wants back into your life. Trust me when I say you want to let him. Because if it comes down to it, you will regret everything that led up to this moment when you have to see him on his deathbed or look up at him from yours.”

The pain in John’s eyes and words as he spoke was enough to crack Sherlock. Harry had gone last year. John was refusing to let him repeat the same mistakes.

Much to Stephens surprise, Sherlock listened to the shorter man, and stood up, flinging his arms round his brother, who hugged him back tentatively but firmly once he adjusted himself. “I forgive you Stephen, I’m sorry too.” His words were broken and shaky, he spoke them as if they hurt him to say but the doctor could tell that he meant every word.

Stephen pulled away, holding out his hand for Sherlock to shake. “My name is Dr. Stephen Stark, I'm a sorcerer but my husband calls me a wizard and my son calls me a time-lord.”

“My name is Sherlock Holmes, people say I'm a psychopath, what I am is a high-functioning sociopath, and my boyfriend insists I'm an otter with too many emotions and no clue how to show them.” He offered a sheepish smile, shaking Stephens hand before the elder twin pulled sherlock against him again. 

“You’re underweight.” The doctor muttered, and Sherlock grinned into his shoulder before pulling away, arms folded.

“You’ve been working out. On note of appearance, what’s with the silly costume?” Sherlock replied.

“What’s with the funny hat?” Stephen replied, tilting his head to the side in a taunting fashion, and Sherlock rolled his eyes. “I joined a cult. Speaking of which, I have to get back to the sanctum.” He spoke gently, as a barista handed him a coffee and he handed the barista some cash.

Sherlock didn’t question it, and John did his best to hide the look of confusion on his face as the other doctor walked away, his robes and cape swishing behind him.

“Stephen.” The doctor turned around at the door, to phase him, an eyebrow quirked up in questioning. “My number, its on the website, we’re here until Thursday, keep in touch?”

“Of course.”

 

They ended up in a swanky apartment building after Sherlock had received a phone call and excitedly told John to get dressed, pulling him into a kiss with both his hands before running to jump in the shower.

The case had since been solved, the elderly neighbour was the culprit, and Sherlock had succeeded in annoying every officer of the NYPD that had the unpleasantry of encountering him by the time the case was closed. He was just happy that Sherlock agreed to let them spend the rest of their trip like a normal holiday, a small escape from the tiresome reign of fatherhood.

John had learned after enough time to stop trying to expect things, to throw out everything he knew before he learned. Often that hypothesis proved effective.

But when Tony Stark opened the door to them, he nearly threw up.

His eyes trained immediately to Sherlock, fixating on the curls and tracing to the face again to make sure his vision wasn’t deceiving him. “Uh… Stephen? What did I tell you about time hopping in the house, and when did you shave? You know I prefer the goatee.” Signs of a panic attack began to creep onto the engineer’s appearance, and John dropped Sherlock’s arm, opting to take his hand instead.

“I am aware, that’s why I keep it.”

John jumped as a voice came from behind them, and there was Stephen dressed more casually, simply in jeans, a t-shirt and an overcoat, leather boots hitting the floor as he walked toward them, yet the same odd necklace hung over his chest.

Tony sighed, placing a hand over his eyes as his shoulders relaxed. “Okay now you’re duplicating yourself?”

“I assure you, he isn’t doing… _That_. Nice to meet you Mr. Stark, Sherlock Holmes, and my partner, Dr John Watson.” He offered the shake of his hand to the shorter man, who took it apprehensively.

“Holmes, that name sounds familiar.” The engineer muttered.

Stephen smiled at him, gesturing to the couple. “Anthony, this is my brother, my twin to be exact, if you couldn’t tell. Sherlock, Dr. Watson, this is my husband, Anthony Stark.”

“Call me Tony.” Tony said to them.

“Call me John.” John said to Stephen.

Tony sighed, but smiled anyway, opening the door to them. “Alright, I was expecting guests, but not this. Come on in. Kid! Set the table!” He called back into the apartment.

“How many people Mr Star- Dad?” A voice called back.

“Five, Peter!” Stephen called, suddenly appearing in front of them without even moving.

“Stephen I’ve told you about doing that in the house! I don’t get my suits, Peter doesn’t crawl on the walls, and you don’t manipulate time.” Tony replied, jabbing a finger into the sorcerer’s chest, but Stephen smiled in response, pressing a gentle kiss to his lips.

“You can do that?” Sherlock asked, his grip on John’s hand increasing.

“I told you, I joined a cult.” Stephen replied, smirking, as he set the necklace in a glass cabinet, alongside a glowing circle mounted in glass, and a metal spider shape on a plaque. 

When they walked into the dining room there was a young adult picking up books from the table, he glanced up and his face turned from that of concern, to shock. His hair was simply styled, brown and pushed hastily back with his fingers to keep it out of his eyes, he looked to be in his late teens or early twenties. University age nonetheless. “You’re Sherlock Holmes and Dr John Watson. Dad-S showed me your blog, I didn’t believe him at first, but you really do look the same, huh?”

“Well yes, given that we’re identical.” Sherlock replied, a coy smile on his face, but John offered the boy an eyeroll to let him know he was joking.

“So, John,” Tony spoke, once they were all seated and eating amongst each other. “Considering you’re the most normal here-“

“Oh, I wouldn’t call him that. He’s quite an extraordinary man.” Sherlock cut him off, and he looked quite shocked. John wanted to hit him for it, despite the unusual compliment. He supposed Sherlock was just showing off.

“Of course he is, he deals with you.” Stephen replied, and Peter covered his mouth to hide a laugh.

“Haven’t heard that one before.” Sherlock spoke with a smirk and John could’ve sworn he kicked his brother under the table.

Tony rolled his eyes. “As I was saying, what do you do for a living?”

“Oh uh, I'm a doctor, I used to be in the army actually, but y’know when you’re out getting shot at-“

“You get shot.” The engineer finished for him, and John nodded.

“So now I just work in a regular clinic at St Bart’s, as a stable income for us and Rosie. Running off on cases with this idiot is a side job.” He replied, gesturing to Sherlock who rolled his eyes fondly.

“Who’s Rosie?” Peter asked, blushing immediately as everyone turned to him, having it be the first time he’d joined the conversation.

Sherlock was first to reply. “Our daughter, she does need some sort of proper upbringing after all.” He spoke, and John could barely contain a grin, it had been years and yet that phrase, the usage of the word _our_ still made him smile like he was lovesick. 

Stephen groaned placing his face in his hand. “Don’t tell me you’ve started her on violin.”

“Of course I have.” Sherlock replied, indignant.

“You’ll have her tortured, brother mine.” Suddenly his accent seemed to go, Tony looked at him quite disturbed, Sherlock looked very smug, and Peter looked like he was about to combust with joy at the posh London words that came out of the doctor’s mouth.

John hummed. “I was wondering when the accent would kick back in.”

“I was wondering if he had an accent. Man, of secrets, I swear.” Tony rolled his eyes.

“Christ you don’t know the half of it.”

“Maybe you can tell me. Right, Stephen, you two go catch up, me and John are gonna do some house-husbandly gossip, Peter finish your homework and we’ll do something fun later.” Tony ordered, collecting everyone’s dishes and ruffling his son’s hair. John in his ever present need to help, picked up some glasses and followed the engineer into their kitchen, but not before Sherlock made the effort to kiss his cheek.

“So,” Tony started, as he began to load the dishwasher, John stood idly with his glass of Pepsi in hand, oh what he would give for a cup of tea, they had a distinct lack of Tetley in America. “How did you meet Sherlock?”

“I got invalided home. Needed a place to live, a mutual friend of ours… Well he’s my friend, Sherlock ‘doesn’t have friends.’ He introduced us. Sherlock knew my entire life story in a matter of minutes and I was gone on him just as quickly. We ended up getting a flat share after I saved his life.” John replied, slightly surprised when the life-saving wasn’t the part that peaked Tony’s interest.

“What do you mean he knew your life? Are they _both_ magic?”

“I think it’s just yours.” John laughed. “He’s a consulting detective, only one in the world as he likes to brag, so he can deduce you in seconds and embarrass you not long after. I learned a bit from him.”

“So, what can you tell about me?”

“You have PTSD and an anxiety disorder.” John replied simply.

Tony’s eyes widened, and he stood up to face John properly. “ _How_ can you tell that?”

“You looked terrified of me and Sherlock when you opened the door, you immediately looked at me holding his arm and panicked thinking I’d kidnapped Stephen or something. Your shoulders raised, your knuckles went white on the door and your eyes dilated.” John spoke calmly, it was never his intention to freak anybody out, that was Sherlocks job. “I have it too, I know the signs. I take it yours doesn’t do deductions.”

“No, he just fucks with time.” Tony laughed, running the sink to wash the bigger dishes used for cooking, and John managed to locate the drying cloths, in an ever present need to be useful or try to be.

“So you’ve told me. How did you two meet?” John asked absentmindedly, as he began drying the dishes the other man cleaned. Their conversation truly becoming house-husbandly gossip.  

“At the start of the war. He was with Banner and Wong, did some wizard shit. Just him with his cheekbones and pulling up his collar to seem cool, and us mutated or shielded in armour, fighting against aliens. In the end me, him, and Peter got stuck on a spaceship. ”

John chuckled softly, but not in a rude way. “Bit different to my day.”

Tony joined him in the soft laughter. “You have no idea. But he swore he’d let me, and the kid die if it came down to us or the necklace. He gave the necklace to save my life in the end. He died, Peter died.”

“I died.”

“You did?”

“Yeah, we were on a case, the guy shot me but I crumbled before it hit. The bastard freaked out and legged it, and Sherlock collapsed until Lestrade found him crying on the street where I fell. The only time I’ll be thankful for Mycroft is when he kept him alive for me. He near drove himself insane looking for an answer.” John replied, he was keen to leave out the fact that he’d seen Sherlock die long before, and that the genius had tortured himself thinking it was John’s way of getting him back for it.

Tony gave a hum in the back of his throat. “Mycroft, he kidnapped me you know.”

“I don’t doubt it, I got the same treatment don’t worry. He used reverse psychology to ensure I was loyal.”

“He threatened to tear me apart if I hurt Stephen.”

“That sounds like him. He practically is the British government.”

“No kidding.” Tony shook his head. “I threatened the Mandarin but some posh dick in a three-piece-suit scared me.”

“He has that effect, it works on babies and children too.”

“Hey Dad-T?” A voice came from the doorway, and John looked up as did Tony.

“What’s up kid?” Tony asked, smiling at Peter, who was twisting his fingers together nervously, John figured he had a more obvious anxiety issue, or he was just shy in personality.

“I was thinking, cause I’ve finished my coursework, that uh- When Dad-S is done talking to Sherlock we could do something all together? Because I kinda want to get to know them too.” He avoided eye contact with either man, and John couldn’t help but smile.

“You’ve done your coursework?” Peter nodded. “Done it all, no worries?” Peter nodded again. “I’ll check it later, what did you have in mind?”

“I thought maybe a board game or something.”

“Sound alright to you?” Tony turned to John, and Peter looked at him hopefully.

“Young man, as long as it’s not Cluedo, I’d be delighted.”

 

Meanwhile Sherlock and Stephen were stood out on the balcony, staring across the city.

When they were kids they used to do something similar. When the one couldn’t sleep, he’d wake his brother up, and they’d sneak onto the roof to watch the stars until they got tired. It worked effectively.

Neither knew that the other had continued the tradition even after they separated. Always brought down from whatever height by a concerned lover.

“Let me see your hands Stephen.” Sherlock spoke, the deep rumble of his voice coming from nowhere, interrupting the silence.

Stephen complied, knowing exactly why, turning to him, and placing shaky, scarred hands in his brother’s firm and grounding grip. Sherlock looked over the scars, tracing over them with his eyes as he’d done the other day at the café.

“From your car crash.” He noted, glancing up, keeping Stephen’s hands in his own.

“You knew about that?” It felt nice to hear his bother talk in his proper accent again, whilst the American drawl Stephen had come to use was a good way two differentiate the two, hearing the British words fall from his mouth filled Sherlock with nostalgia and warmth.

He was at home with John, no matter where they were. But Stephen was still his brother, even after all this time.

“I saw it on the news. I begged Mycroft to tell me more about it, practically on my knees, resorted to bargaining, but nothing worked.” Sherlock replied, his tone nonchalant. But Stephen knew Sherlock’s face like he knew his own, and there was pain hidden behind the neutral mask he was desperately tugging at to keep on. “I couldn’t take much more interest than that, John would’ve gotten suspicious, and I’m sure his reaction was unpleasant when he saw you. He hates when I keep things from him.”

“I told that bastard to tell you I was okay. You’d blocked my number and my letters always came returned. I fucking trusted him.”

“What a git.” Hidden under his tone was an apology.

As simply has his hands had been in Sherlock’s, they were at his sleeves, pulling them up with swift precision, revealing the healed over scabs from where needles had entered and withdrawn. “Lockie…” His voiced was filled with pain, his eyes just as much as he looked up at Sherlock in concern, and the detective looked back in regret.

“I'm clean. Two years. Thank John for that, and Rosie when you meet her.” Sherlock replied, letting go of his brother’s hand and turning back to the balcony. “So, sorcery, what’s that all about?”

“I wanted to get my hands to work again.” Stephen spoke simply. “I wanted to keep being a doctor.”

“They still shake.”

“Yeah, well I found more responsibilities than medicine, than my own selfish wants or desires for things to return to normal. I can’t show you anything, I don’t have my ring or the necklace-“

“ _And_ your husband banned it in the house. Believe me you don’t want to anger him on that, John was furious the last time he caught me smoking.” Sherlock replied, cutting him off. If there was one thing he’d learned from his years of dating John, it was that.

“Somehow I don’t think smoking and spells equate to the same.”

“Considering your son can crawl on walls, I’d say it does.”

“You jealous?”

Sherlock laughed. “God no. Rosamund, she gave me purpose for a while, just her presence in infancy kept me right. I thank her for John and I even getting together in the first place.”

“So she’s not your-“

“John’s wife, Mary, deceased.”

“Ah.”

Sherlock smiled, thinking about his daughter. How she would laugh when he carried her on his shoulders, how excited she got when John returned home after a shift. “I love her so much, Stephen. She’s amazing, and brilliant and I don’t think you understand the pride when she brings home a spelling test with everything right. It seems stupid but it’s wonderful.”

To his utmost surprise, Stephen didn’t tease him about it, he nodded. “I didn’t want kids. I was content on being a bachelor doctor with an eidetic memory.”

“You kept the memory.” Sherlock offered in an attempt to be comforting, but he supposed the coy smirk that crept onto his face wasn’t helping his case.

“Peter’s parents were dead long before Tony or I were in his picture. He lived with his Aunt, but about the time when Tony and I first got together, taking care of Peter got too much for her, and Tony jumped at the chance to take him in. He didn’t ask me, he still hasn’t asked me. But I don’t care. The kid’s a genius.” Stephen smiled fondly as he stared out over the balcony.

“You’re Dad-S, I take it Tony is Dad-T?”

“Indeed. What does Rosie call you?”

Sherlocked hummed before replying. “John’s always been Daddy or Dad. She alternates from calling me Papa and Da. I was Papa when we left though.”

Stephen smiled shaking his head, as they looked out over the city. “Do you think we’ve gone soft?”

“Who are you? Mycroft? _Redbeard, Sherlock._ ” Sherlock mimed the flick of an umbrella and scrunched up his face into an unflattering position. Stephen laughed, his eyes crinkling with genuine Joy as he doubled over in a fit of giggles.

“I think yes, we have gone soft.” Sherlock mused once his brother caught his breath again. “Don’t you love it though?”

“God yes.”


End file.
